The present application claims priority to European Procedure (EP) Application Serial No. 16305414.1, filed on Apr. 8, 2016, which is incorporated herein by reference in its entirety.
The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
The present disclosure broadly relates to metal bonding, cement and cementing operations.
Hydraulic cement is any substance provided (at least at one time in the manufacturing process) in a powdered or granular form, that when mixed with a suitable amount of water, can form a paste that can be poured or molded to set as a solid mass. In the oil and gas industry, good bonding between set cement and casing is essential for effective zonal isolation. Poor bonding limits production and reduces the effectiveness of stimulation treatments. Communication between zones can be caused by inadequate mud removal, poor cement bonding, expansion and contraction of the casing resulting from internal pressure variations or thermal stresses, and cement contamination by drilling or formation fluids. Under such circumstances a small gap or microannulus may form at the cement/casing interface.
Attempts have been made to improve the bonding between the well casing the cement. For example, U.S. Pat. No. 7,650,940 is generally directed to the inclusion of carboxyl groups in particulate elastomers in a cement composition to enhance adhesion between the cement composition and the casing and/or the wall of the subterranean formation. U.S. Pat. No. 4,716,965 is generally directed to providing a layer of elastomeric foam on the outside of the casing, which is alleged to remain resilient and retain structural integrity of the cement sheath after being compressed between the casing and the cement. However, the foam is expensive, easily damaged, and adds a significant amount of thickness to the casing.
The industry in general is in need of ways to improve the bond between cement and metal members in general, to improve the bond between the cement and the casing or other tubular member within the well annulus, as well as ways to prevent a microannulus from forming between the casing or other tubular member and the cement sheath.